replacing leaking Harley-Davidson fuel line and check valve quick disconnect o-rings (2023)


Here's a quick video of what I did to replace the fuel tank check valve quick disconnect o-rings on my fuel injected 2012 Harley Dyna Wide glide. It should be similar on 2000 and newer fuel injected Harley's. I used the Fuel Tool rebuild kits. One kit for the hose and one for the check valve. I recommend not using the lower oring that comes with the check valve kit. All of the other orings fit fine. Instead use a 10mm x 14mm x 2mm for the lower oring, the one in the kit is slightly undersized and leaked for me. From what the forums say, the upper should be ID .299", thickness .103", OD .505", but for this one I just used what was in the kit. I also used dental picks for removal and a 9/32 socket as a tool to push in the parts. From what ive read the hose oring is .37" OD x .19" ID .09" thickness, which is roughly the same as a 3/8" OD x 3/16" ID. For the hose oring I just used what was in the kit. Fuel Tool sells a tool for rebuilding it but it is $100. I bought the 2 rebuild kits from J&PCycles website for about $30 total. The Fuel Tool part numbers are MC300 for the check valve and MC700 for the fuel line.
On an after thought, the resistance that I was feeling may be that the valve needs to be aligned to get it to pop in. If you run into the same problem you may just need to rotate the valve part until its aligned and its should all pop right in using the socket. I hope this video helps someone. Good luck!


Okay, so I bought these two kits from uh fuel tool, uh, I think I actually got it through amazon, but uh, these kits here.


This one here is for the check valve that's on the tank.

This one's for the o-rings for the fuel line.

This one fit fine the one for the check valve on the tank, the everything was good on it, except for the lower o-ring that's.

The one that keeps it from leaking outside of the uh, the hoses and check valve that one did not fit correctly.

Uh, it went in, but it still leaked.

So I was reading a lot online and there's a harley part number here, but I didn't end up using it.

The size of the harley part number is actually the same from what I've been reading as a 10 millimeter by 14 millimeter by two millimeter.

Uh, I think the one that they sent in this kit is probably 9 16 by 7, 16 by 16 inch and uh that one I put it in and it leaked.

So go ahead and go to uh, go to autozone that's where I found it.

Uh, it comes in this kit here, metric o-rings.

And it was the exact size the 10 millimeter 14 by two.


So what I did is I took off the seat.

First took apart the console.

These bolts here unplug that to disconnect the fuel pump power.

And you want to try and crank it over it's going to depressurize this line here allow you to disconnect it.

And then all you're going to do is well it's going to it might start.

It might not, but try it a few times if it does start let it run for a second until it dies.

So it'll depressurize this line and you lift up on the collar here.

And now you'll be able to disconnect it without worrying about any pressure in there.

So after I did that I went ahead and uh, siphoned as much out of the tank as I could drained out whatever fuel I could and then, um, went ahead and disconnected.

The battery and started, uh, pulling out the uh o-rings and the parts inside here.

So one thing I use to get these, uh, o-rings removed and help to replace them is just these dental picks helps putting everything back in a lot easier in uh, removing it too.


So you want to stack them in this order here, the fat end of the spring, the valve the larger fat o-ring and a larger diameter at the bottom.

So you just kind of stack them in that order.

And I found that a uh, 9 30 seconds, quarter inch, drive socket.

Uh is the same diameter as the end of your fuel line.

So that you can use instead of uh use that as a tool to slide it in there.

I also sprayed a little bit of the wd-40 inside to make it a little easier.

So basically you want to stack it like this with the larger end of the spring in then the valve, and then the fat o-ring, you put it in the socket, and then put it up inside the uh check valve.

So once I get it up, there, you'll, see, there's, uh, if you can see this, but there's, two, two slots for the o-ring up in there kind of hard to see, but uh, you want the fat o-ring to be up at the very top.

I could probably see it there now, um.

So you got to pull up on the collar when you install it.

And at first, you might have a hard time using the socket.

So I just kind of use this to probe something with a blunt end.

You don't want to cut the o-ring and just kind of feed it around.

And then use a socket to push it in the rest of the way, and it pops right in.

So when you go to put this thing in uh, you're going to feel some resistance, um, when you put it up in there, you gotta get this.

Uh centerpiece here.

You gotta push up on it and it'll pop in place.

You compress the spring.

Okay, um after that.

Then you can put in the socket and then try and feed in the uh feet in the o-ring, but you're gonna feel a lot of resistance until you get that chrome piece, the valve pushed up a little further.


So, um, that's.

What it looks like when you get the valve in and the upper o-ring and the lower o-ring.

So to get the lower o-ring in the skinnier one, I used this head of a nail and a little tedious, but I kind of worked around around the inside of that to get to sit in the groove like that.


So this is the uh hose side, that's how it goes in.

So I just picked out all the guts.

I actually bought this kit, because I had lost the little valve that fell out rolled along the floor, and I lost it.

But um.

So you just kind of feed it in in that order.


So this is what it looks like when it's in installed, uh.

So it actually tells you here in this little paper that comes with the kit to install it.

You, uh, rotate it into like a figure eight twist it with your thumb.

And then, uh, I just pushed in on the on.

The valve got one side in with it shaped like a figure eight and just kind of worked it around.

And eventually you get it in there.

So after you get that together, uh, just go ahead and connect it and reconnect it, uh, disconnect it and just cycle it.

A few times make sure everything's good and crank her up and should be good to go.

Good luck.


Replacing leaking Harley-Davidson fuel line and check valve quick disconnect o-rings? ›

Fuel check valves are installed in fuel lines. They allow fuel to only flow in one direction and prevent lines running dry, for example.

Can you put a check valve in fuel line? ›

Fuel check valves are installed in fuel lines. They allow fuel to only flow in one direction and prevent lines running dry, for example.

What are the symptoms of a bad fuel check valve? ›

For example, failing check valves will start to vibrate and even lose some internal parts when problems begin to arise. Other symptoms of check valve failure include reverse flow and excessive component wear and damage. Check valves will also emit noises as they start to break down.

Does a gas line need a check valve? ›

Improper flow of gas can lead to potentially dangerous problems like leakages, contamination of the gas, and even explosions and fires. To reduce the occurrence of these problems, gas transmission specialists utilize check valves daily.

Can you use Flex Seal on fuel line? ›

A: No. We do not recommend using Flex Tape on a gas or oil tank.

Do fuel lines need sealant? ›

Sealing Fuel Fitting Threads

A frequently asked question from DIY boaters is how to seal the pipe threads found on fuel system components. For most components such as a pre-fuel filter (aka fuel water separator) the thread type is typically NPT or NPTF and requires sealant around the threads.

Do fuel lines need to be bled? ›

And yes, if there's air in your fuel lines, the lines need to have that air bled out. Smaller amounts of air will cause all sorts of performance issues, while too much air in your fuel lines will prevent the engine from even starting.

What is the pressure at the fuel check valve? ›

Parameter: Min upstream pressure:0.2bar(2.9psi),working pressure range: 0.2-6bar (2.9-87psi),operating temperature range: -22℉ to 266℉. Application: The fuel line check valve is widely uesd in vacuum system,carburetors and low pressure fuel systems.

Do you put a check valve before or after? ›

The check valve must be installed before the outlet control valve at the pump's outlet so that it can be repaired. In general, the pump's first outlet is a soft connection (shock absorber), followed by a check valve, and finally a block valve (such as butterfly valve, gate valve, globe valve, etc.)

What is the best gas for Harley Davidson Road King? ›

The majority of motorcycle engines, including all current Harley-Davidson engines, require 91 octane or higher (Premium) fuel, thanks to high compression ratios.

Should I extract gas out of tank before removing gas tank from motorcycle? ›

Just make sure it's not going to tip over when you're working on it. Remove the fuel. Removing the gas tank will be safer and easier if you remove all of the fuel. You can do this by running it down or siphoning it out.

Why does my Harley bog down when I accelerate? ›

The most common reason is that your air/fuel mixture is inefficient or dirty. If your air filter is clogged or has a lot of dirt. It could be bogging down the engine.

Does it matter where you put the check valve? ›

The best practice is to place the check valve outside the aquarium (not in the water), close to the top of the fish tank. This position stops the water at the rim rather than near the air pump where the water pressure in the airline tubing could cause a leak.

Where do you put an inline check valve? ›

Another instruction from the bronze pressure reducing valve manufacturers is that the check valve must be installed at the outlet of the pump and in front of the outlet control valve for maintenance.

Can a ball valve be used in a gas line? ›

Ball valves are ideal for controlling the flow of liquid or gas through a system. The rotary ball within the valve stops the flow of material when the valve reaches a specific state. Ball valves perform well in low-flow situations, throttling vapors and gases in hydrocarbon processing applications.

Can I use a check valve instead of air gap? ›

Although alternative methods are available, only an air gap is approved by the plumbing code, because it is the only method guaranteed to work in all circumstances. * A check valve is also an anti-backflow device and will also prevent sewage from siphoning into your dishwasher.

Top Articles
Latest Posts
Article information

Author: Kareem Mueller DO

Last Updated: 10/07/2023

Views: 5357

Rating: 4.6 / 5 (66 voted)

Reviews: 81% of readers found this page helpful

Author information

Name: Kareem Mueller DO

Birthday: 1997-01-04

Address: Apt. 156 12935 Runolfsdottir Mission, Greenfort, MN 74384-6749

Phone: +16704982844747

Job: Corporate Administration Planner

Hobby: Mountain biking, Jewelry making, Stone skipping, Lacemaking, Knife making, Scrapbooking, Letterboxing

Introduction: My name is Kareem Mueller DO, I am a vivacious, super, thoughtful, excited, handsome, beautiful, combative person who loves writing and wants to share my knowledge and understanding with you.